Multi-use paving tractor with tool attachments

ABSTRACT

A multi-use asphalt paving tractor with interchangeable attachments for performing the functions of a paver, a mix transfer conveyor and road widener.

BACKGROUND OF INVENTION

In the past, road paving equipment designers have endeavored to improve the functionality of road pavers. U.S. Pat. No. 6,007,272 is an example of an improved paver with mixing capabilities. While such improvements have been made to remixing capabilities of pavers, they remain a single use machine. Most paving contractors will have a paver, a road widener and some means for transferring the mix to the paver and road widener, all of which are independent machines.

While these approaches of using independent pavers, road wideners and mix transfer machines, etc. have been used extensively in the past, they do have some drawbacks. First of all, they require significant investment. Secondly, they require considerable space for storage and transportation.

Consequently, there exists a need for improved methods and systems for deploying multiple paving equipment tools.

SUMMARY OF INVENTION

It is an object of the present invention to provide a system and method for deploying multiple paving equipment tools in an efficient manner.

It is a feature of the present invention to utilize a multi-use paving tractor.

It is an advantage of the present invention to reduce the cost of owning a group of paving tools.

It is another advantage to permit multiple paving equipment tools to be stored in a smaller space.

It is yet another advantage to permit reduced transportation costs in moving several paving tools to a job site.

The present invention is an apparatus and method for deploying multiple paving tools, designed to satisfy the aforementioned needs, provide the previously stated objects, include the above-listed features, and achieve the already articulated advantages. The present invention is carried out in a “redundant hardware-less” manner in a sense that the need to own, maintain and transport multiple paving hoppers, remixing equipment and propulsion mechanisms for a group of road paving tools, has been eliminated.

Accordingly, the present invention is a system and method including a paving tractor with a capability for readily connecting and disconnecting a road paving tool thereto.

BRIEF DESCRIPTION OF DRAWINGS

The invention may be more fully understood by reading the following description of the preferred embodiments of the invention, in conjunction with the appended drawings wherein:

FIG. 1 is an elevation view of the multi-use paving tractor of the present invention, with a partial cut-away portion to reveal a plurality of augers.

FIG. 2 is an elevation view of the paving tractor of FIG. 1, having an attached mix transfer tool.

FIG. 3 is an elevation view of the paving tractor of FIG. 1, having an attached road widener tool.

FIG. 4 is a partial top view of the paving tractor and road widener tool of FIG. 3.

FIG. 5 is an elevation view of the paving tractor of FIG. 1, having an attached screed.

DETAILED DESCRIPTION

Now referring to the drawings wherein like numerals refer to like matter throughout, and more specifically referring to FIG. 1, there is shown a multi-use paving tractor of the present invention, generally designated 100, which includes a hopper and mixing apparatus 101, a conveying shaft 102, auger 109, driver station 120, driver seat 122, steering wheel 124, engine 126, chassis 127 and drive train 128. Items 101, 102, 109, 122, 124, 126, 127 and 128 are preferably similar or identical to components of prior art remixing road pavers such as described in the above-referenced U.S. patent and the prior art road paver manufactured by Cedarapids, Inc. of Cedar Rapids, Iowa. Engine 126 is drawn as a simple block, but it may include numerous related systems and/or components not limited to components of a hydraulic pump and system, an electrical system and other systems. One of the key aspects of these prior art pavers is that they do not exhibit the characteristics of dropping or dribbling asphalt from a return conveyor under the machine as is common in other prior art pavers. The elimination of dribbling from underneath the prior art paver was not perceived as a significant benefit because that machine and the machine described in the above-referenced patent were both dedicated pavers. Dribbles on the ground in front of a paver were not a problem because the paver covered these dribbles as the paver progressed forward. However, for the present invention, it is desirable that the tractor 100 not dribble asphalt on the ground as it progresses forward. The non-dribbling configuration of the above-referenced patent and the above-described paver is preferred. However, it should be understood that any other non-dribbling or low-dribbling mechanisms could be used in conjunction with the remainder of the present invention.

A pull arm 103 is shown coupled to the tractor 100. Preferably a pull arm 103 is disposed on each side of the tractor. Pull arm 103 may include a quick connector 1032 disposed on or near a rear end 1031 of the pull arm 103. Pull-arm quick connector 1032 could be numerous types of connectors, such as a butt plate with holes for receiving bolts or pins, a channel for receiving an insert dropped in from above, a male or female connector, etc. Pull arm quick connector 1032 may have additional connectivity capability beyond structural connections, such as electric connections, hydraulic hose connections, etc. In any case, it is preferred that pull arm quick connector 1032 provide for the ability to add or remove attachments very quickly and while in the field. Preferably, no welding or powered tools, other than those receiving power from the multi-use paving tractor 100 and a lift used to move the attachment, would be necessary. Hydraulic cylinders 1034 and 1035 or other mechanism for manipulating pull arm 103 between various raised and lowered positions are also shown. In a preferred arrangement, the pull arm 103 can be raised or lowered to engage tool attachments, discussed in detail below. While it may be preferred to utilize dual pull arms 103 on each side, it should be understood that a centrally disposed pull arm or group of centrally disposed pull arms could be used as well. The pull arm 103 is preferably movable, but it should be understood that it could be a simple fixed connection point disposed on the tractor 100. An upper link 104 could be another connection between the tractor 100 and tool attachments. Upper link 104, if hydraulically extendable and retractable, could be used to connect, position and otherwise manipulate any tool attachment coupled to pull arm 103. (Note: that the upper link 104 may not be used on some attachments such as the screed.) An upper link 104 may be disposed on either side of the tractor 100, or a single upper link could be used as well. Appropriate driver controls 125 may be included to assist in the manipulation of pull arm 103 and upper link 104.

A more detailed understanding of the present invention can be achieved by now referring to FIG. 2, which shows a multi-use paving tractor 100 of FIG. 1, together with an HMA mix transfer tool attachment, generally designated 200, which includes an elevator assembly 205, which collects remixed HMA from the rear of conveying shaft 102 and hopper and mixing apparatus 101 and elevates the HMA. Elevator assembly 205 includes elevator assembly lower connecting floor 206, which seals the elevator assembly 205 to the rear of the conveying shaft 102. Elevator assembly lower connecting floor 206 is where the HMA is collected prior to being elevated above the conveying shaft 102 by the elevator assembly 205. Elevator assembly slat conveyor 207 is shown disposed in elevator assembly 205. It should be understood that the depicted arrangement of elevator assembly 205 is a preferred embodiment of the present invention. Alternate means and methods of elevating the HMA could be employed, such as augers, pumps and pipes or hoses, etc. The purpose of elevator assembly 205 is to collect the HMA and deliver it to swinging slat conveyor 209. However, it should be understood that elevator assembly 205 or its alternate means could be adjustable vertically and radially so as to eliminate the need for swinging slat conveyor 209.

In this preferred embodiment, swinging slat conveyor 209 is a vertically and radially adjustable conveyor which can be swung to the right or the left upon swinging slat conveyor pivot support 211, which can be a hinge or other pivot support. Swinging slat conveyor 209 includes a swinging slat conveyor interior chain assembly 208 and a swinging slat conveyor raising mechanism 210 which can be disposed on one pull arm 103 or one side of the multi-use paving tractor 100, or it can have one on each side of multi-use paving tractor 100 or attached to right and left pull arms 103. Swinging slat conveyor raising mechanism 210, if mounted to a side of multi-use paving tractor 100, can both raise swinging slat conveyor 209 and swing swinging slat conveyor 209 right and left as needed. Swinging slat conveyor raising mechanism 210 can be a hydraulic cylinder, a cable/winch system or other system for lifting and swinging the swinging slat conveyor 209.

Swinging slat conveyor pivot support 211 is preferably a support for pivoting about a horizontal axis and a vertical axis. A rotational coupling or independent orthogonal pivots could be used to enable swinging slat conveyor 209 to be both raised and swung as needed.

An even more detailed understanding of the present invention may be achieved by now referring to FIGS. 3 and 4, which shows a right- or left-sided road widener attachment 300, which is preferably attached to multi-use paving tractor 100 via pull arm 103. In this figure, elevator assembly 205 is used to elevate the HMA for distribution to a chute or cross conveyor 302. The HMA is then distributed alongside the multi-use paving tractor 100 so as to provide for road widening by road widener strike-off blade 417. The road width extension dimension 414 can be adjusted by manipulation of road widener strike-off blade angle control link 415, which controls the angle of road widener strike-off blade 417. The HMA is partially contained by road widener end gate assembly 413, which is adjusted by manipulation of road widener end gate angle control link 416. Right- or left-sided road widener attachment 300 is shown with few details because it is believed that numerous right- or left-sided road widener attachments 300 could be designed to meet the peculiar needs for various road types. It is believed that a person skilled in the art of making road wideners could readily adapt the above-described concept to work with most any particular road widening project type. For example, road widener strike-off blade 417 could be made to pivot about both a horizontal axis and a vertical axis.

FIG. 5 shows a multi-use paving tractor 100 with a paver screed 518 attached thereto. It is believed that one skilled in the art given the description of the present invention could develop various paver screeds 518 to meet particular needs of various paving job types.

In operation, the apparatus and method of the present invention as described in FIGS. 1-5, could function as follows:

Firstly, a multi-use paving tractor 100 is provided which accepts HMA in a hopper and mixing apparatus 101 and transports it rearward via conveying shaft 102.

One of several attachments, such as HMA mix transfer tool attachment, right- or left-sided road widener attachment 300 or paver screed 518 could be attached to the multi-use paving tractor 100, depending upon the needs at the time. The combination is then deployed and used on a road. The attachment then is removed and replaced with another of the several attachments and the new combination is used. Numerous road-paving tools can be deployed on one job without the need for redundant components. The removal and replacement process preferably can be done by either using a lift to pick up the attachment or raising the attachment and backing the multi-use paving tractor 100 to a trailer or platform where the attachment is then lowered and disconnected.

Throughout the above description, HMA is described as the material to be used. It should be understood that the present invention is directed to any type of road surface. It is believed that recycled asphalt products could be used, cold mix asphalt, and even in certain applications with any appropriate modifications, concrete could be the paving material. Hopper and mixing apparatus 101 may comprise a rectangular box or an angled rectangular or circular bin or any shaped container and material mixing and transfer apparatus which is suitable for the paving material being used.

It is thought that the method and apparatus of the present invention will be understood from the foregoing description and that it will be apparent that various changes may be made in the form, construct steps, and arrangement of the parts and steps thereof, without departing from the spirit and scope of the invention or sacrificing all of their material advantages. The form herein described is merely a preferred exemplary embodiment thereof. 

1. A road paving tractor comprising: a chassis having a front end and a rear end; a hopper disposed on said chassis at said front end; a driver station comprising a driver seat and a steering wheel; said driver station disposed on said chassis at said rear end; an engine and drive train coupled to said hopper and configured to provide propulsion of said hopper, said chassis, and said driver station, when said hopper is filled with road paving material and said driver station is occupied by a driver; means for moving paving material from said hopper toward said rear end, such that said paving material is not dribbled below said tractor as a material conveyor loops underneath said tractor; an attachment coupling means coupled to said chassis, and toward said rear end; said attachment coupling means being configured so as to have an adjustable location with respect to said chassis; said attachment coupling means configured to temporarily receive one of a plurality of detachable road paving tool attachments; and, said chassis, said hopper, said engine, said driver station, and said means for moving paving material being free from attachment to any paving screed, road widening strike-off blade, and radially and vertically adjustable material mover, of a type configured to move paving material at an upward angel away from said rear end, when said attachment coupling means is not coupled to any of said plurality of detachable road paving tool attachments.
 2. The road-paving tractor of claim 1 further comprising a paving screed attached to said attachment coupling means.
 3. The road-paving tractor of claim 1 wherein said attachment coupling means is configured to operatively mate with each of said plurality of detachable road paving tool attachments without a need for welding to occur during a process of mating a detachable road paving tool attachment to the road-paving tractor.
 4. The road-paving tractor of claim 3 further comprising a mix transfer tool attachment.
 5. The road-paving tractor of claim 4 wherein said mix transfer tool attachment is a hot mix asphalt transfer tool attachment.
 6. The road-paving tractor of claim 5 wherein said mix transfer tool attachment comprises a means for elevating hot mix asphalt.
 7. The road-paving tractor of claim 5 further comprising a swinging slat conveyor and a swinging slat conveyor pivot support which provides support from below for said swinging slat conveyor and permits said swinging slat conveyor to rotate about a horizontal line and about a vertical line.
 8. The road paving tractor of claim 7 further comprising a swinging slat conveyor-raising mechanism.
 9. The road paving tractor of claim 8 further comprising an elevator assembly coupled to said rear end for receiving hot mix asphalt and for elevating said hot mix asphalt above an asphalt receiving point on said swinging slat conveyor while a distal end of said swinging slat conveyor is elevated with respect to said asphalt receiving point.
 10. The road paving tractor of claim 3 further comprising a road widener attachment comprising a road widener strike-off blade and a road widener end gate, a road widener end gate angle control link, and a road widener strike-off blade angle control link.
 11. A method of deploying multi-use road paving equipment comprising the steps of: providing a paving tractor with a first detachable road paving tool attachment operatively coupled thereto at a first connection point, where said fist connection point is on a adjustable pull arm, which is adjustably positioned with respect to a chassis of said paying tractor; replacing said first detachable road paving tool attachment with a second detachable road paving tool attachment without welding or cutting metal at said first connection point; where said first detachable road paving tool attachment is configured to perform a substantially different task than said second detachable road paving tool attachment; and, wherein said paving tractor is a self-propelled vehicle configured to be driven by a driver located on and at a rear end of said paving tractor, said paving tractor or further comprising a hopper disposed forward of said rear end, and means for conveying paving material from said hopper to said rear end.
 12. The method of claim 11 wherein said step of replacing comprises the steps of: causing said first detachable road paving tool attachment, while coupled to said paving tractor, to be disposed over a structural member disposed higher a tractor operating surface upon which said paving tractor is disposed; causing a vertical separation between said structural member and said first detachable road paving tool attachment to decrease; and, separating said first detachable road paving tool from said paving tractor.
 13. The method of claim 12 wherein said step of causing a vertical separation is accomplished by a manipulation of said adjustable pull arm.
 14. The method of claim 13 where said step of replacing further comprises the steps of: mating said second detachable road paving tool attachment to said vertically adjustable pull arm; and, using a lifting force assisted by an engine onboard said road paving tractor to lift said second detachable road paving tool attachment.
 15. A multi-use road paving system comprising: a road paving tractor comprising: a chassis, having a front and a rear end; a hopper for receiving and containing road paving material, disposed at and coupled to said front end; a plurality of paving material moving augers disposed, at least in part, in said hopper, for moving paving material from said hopper toward said rear end; an engine, coupled to said chassis, for providing motive force to propel said road paving tractor; a vertically adjustable arm, coupled to said chassis for providing movement of a connection point thereon; a hydraulic system, coupled to said chassis, and receiving power from said engine, said hydraulic system for assisting vertical adjustment of said vertically adjustable arm; a plurality of detachable road paving tool attachments, each configured to mate with said connection point, such that a manipulation of said vertically adjustable arm, via said hydraulic system, results in at least a vertical displacement of any detachable road paving tool attachment coupled thereto; said plurality of detachable paving tool attachments each farther configured, when coupled to said vertically adjustable arm, to cause road paving material, in contact therewith, to be relocated in a predetermined manner; and, said plurality of detachable paving tool attachments each further configured so as to be operatively attachable to and detachable from said connection point without either of welding and cutting, any structural metal components of at least one of said road paving tractor and a detachable paving tool attachment.
 16. The multi-use road paving system comprising: a road paving tractor comprising: a chassis, having a front and a rear end; a container for receiving and containing road hot mix asphalt paving material, disposed at and coupled to said front end; means for moving said hot mix asphalt paving material from said container to said rear end; an engine, coupled to said chassis, for providing motive force to propel said road paving tractor; said chassis comprising a connection point having an adjustable location with respect to said chassis, a detachable road paving tool attachment configured to mate with said connection point, such that a movement of said road paving tractor results in at least a horizontal displacement of said detachable road paving tool attachment coupled thereto; said detachable paving tool attachment further configured, when coupled to said connection point and moved along with said road paving tractor, to cause said hot mix asphalt road paving material, in contact therewith, to have a top surface with an increased smoothness characteristic; and said detachable paving tool attachment further configured so as to be operatively attachable to and detachable from said connection point without either of welding and cutting any structural metal components of at least one of said road paving tractor and said detachable paving tool attachment.
 17. The road paving system of claim 16 further comprising a lift system, coupled to said chassis, and receiving power from an engine, said lift system for assisting vertical adjustment of a vertically adjustable arm, said vertically adjustable arm configured such that a vertical adjustment results in a vertical displacement of said connection point.
 18. The road paving system of claim 17 wherein said lift system is a hydraulic system and said detachable paving tool attachment is a screed.
 19. The road paving system of claim 18 further comprising a road widener configured for attachment to said connection point when said screed is not coupled to said connection point.
 20. The road paving system of claim 19 wherein said road paving tractor further comprises a driver station comprising a seat and hydraulic controls. 